1. Field of the Invention
This invention relates to a method and apparatus for producing a sheet of dough. It especially relates to a method and apparatus for producing a sheet of bread dough from a dough mixture that consists of powdered materials, including flour and ice.
2. Description of Prior Art
Many attempts have been made to instantly provide dough of a good quality whenever it is needed. In the prior art methods raw materials are mixed with water and kneaded to form a lump of dough. The lump of dough is extruded from an extruder, and then sheeted, cut and then shaped and fermented to produce dough products.
However, these prior art methods have several problems. Namely, the mixing and kneading process needs operators' skills in judging whether the materials are uniformly mixed with water and whether the gluten in the kneaded dough is sufficiently developed. It has been generally said that within a limited period of time the constant production of a uniform mixture of powder and liquid is difficult. The amount of water for making dough is usually less than that of powdery materials so that the powdery materials tend to gather to form a hard mass. In order to eliminate it, a long period of time for kneading is required. Once dough is kneaded, fermentation starts progressing in the dough due to the yeast contained in it. This fermentation cannot be stopped until the dough is completely baked or is frozen. Therefore, the discontinuation of fermentation before such processes means scrapping the dough. Further, in the above-mentioned kneading process, the network of the tissue structure of a well-developed gluten is liable to be destroyed due to a squeezing force exerted on the dough by the extruder. Hence, an extra process, such as a resting process, is needed to recover the lost tissue structure.